如何在SpriteKit中将Sprite旋转90度

Question

Im trying to add rotation to a sprite by 90 degrees, so if i tap above it, it moves 90 degrees an faces that direction. Think like snake game.

In my touchesBegan method i can get the Sprite to rotate, however it seems to flip itself and not actually go 90 degrees, more like 180.

Any ideas why and how I could get it to point in the correct direction.

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
    let touch = touches.first as UITouch!
    let touchLocation = touch.locationInNode(self)
    sceneTouched(touchLocation)

    if (car.position.x > touchLocation.x) {
        car.zRotation = CGFloat(M_PI_2)
    } else {
        car.zRotation = CGFloat(-M_PI_2)
    }
}

Answer 1

Based on the fact that your code works for me I would say that this is probably happening because the current value of car.zRotation is not 0.0 but rather something like -M_PI_2 . So when you set it to M_PI_2 you get a rotation of 180 degrees. Try to print car.zRotation before you set a new value .